1. Technical Field
The present invention relates to a head-mounted display mounted on a head for use.
2. Related Art
In recent years, various types of displays in which image light from display elements is guided to pupils of eyes of observers by light-guiding plates have been proposed as head-mounted displays (hereinafter also referred to as HMDs) capable of forming virtual images and enabling the observers to observe the virtual images. When HMDs are used to watch movies, it is preferable to have horizontally long aspects. However, for example, HMDs are also used to correspond to images with vertically long aspects, such as images for smartphones. In this case, even when the vertically long aspects are used without conversion, the vertically long aspects can be partially displayed. However, resolutions deteriorate and screens also decrease.
There are known head-mounted displays referred to as HMDs that display images by providing rotation mechanisms in display elements or adjusting aspect ratios by toric optical systems to change the aspect ratios (see JP-A-2013-073188 and JP-A-2013-37095). There is also a known video display apparatus configured such that an image display element and an eyepiece optical system (half mirror) guiding an image of the image display element are integrated and are rotatable (see JP-A-6-70265).
However, these display apparatus may not be said to meet use needs for desiring to display both of an image with a horizontally long aspect ratio and an linage with a vertically long aspect ratio with high resolution and in a good state.